Jami` at-Tirmidhi Book 48, Hadith 162
“O Messenger of Allah, teach me a supplication that I may supplicate with in my Salat.” He (ﷺ) said: “Say: ‘O Allah, I have wronged myself much, and none forgives sins except You. So forgive me with forgiveness from You, and have mercy upon me, indeed, You are the Forgiving, the Merciful (Allāhumma innī ẓalamtu nafsī ẓulman kathīran wa lā yaghfirudh-dhunūba illā anta faghfirlī maghfiratan min `indika warḥamnī innaka antal-Ghafūrur-Raḥīm).’”
“I heard Abu Wa’il say: ‘`Abdullah bin Mas`ud said’ and I said to him: ‘Did you hear it from `Abdullah?’ He said: ‘Yes.’ And he narrated it in Marfu` form that he said: ‘There is none with more Ghirah than Allah, and due to this He prohibited the lewd sins, that which is apparent of them and that which is hidden. And there is none to whom praise is more beloved than Allah, and due to this, He praised Himself.’”
“Al-`Abbas came to the Messenger of Allah (ﷺ) and it is as if he heard something, so the Prophet (ﷺ) stood upon the Minbar and said: ‘Who am I?’ They said: ‘You are the Messenger of Allah, upon you be peace.’ He said: ‘I am Muhammad bin `Abdullah bin `Abdul-Muttalib, indeed Allah created the creation, and He put me in the best group of them, then He made them into two groups, so He put me in the best group of them, the He made them into tribes, so He put me in the best of tribes, then He made them into houses, so He put me in the best of them in tribe and lineage.’”